The present invention relates to an incandescent ignition arrangement for an internal combustion engine.
Incandescent ignition arrangements for internal combustion engines are known in the art. A known incandescent ignition arrangement is combined with a fuel-injection device and has an ignition chamber coaxial with the latter and having at least one overflow passage communicating the ignition chamber with a main combustion chamber and an electrically heatable ignition element. Such an incandescent ignition arrangement is disclosed, for example, in French Pat. No. 1,382,697. The ignition arrangement disclosed in this patent has at its one end an open cylindrical chamber and an electrically heatable ignition element formed as a wire coil and arranged inside the ignition chamber. An injection device with which the fuel is injected into the internal combustion engine is coaxial with the ignition chamber and injects fuel into a main combustion chamber of the internal combustion engine. This main combustion chamber is connected with the ignition chamber via a passage which is simultaneously directed to the injection device. During injection fuel droplets are separated from the injected stream. A part of these droplets is supplied during a compression stroke of the internal combustion engine together with air which is pressed in the ignition chamber, in this chamber. Because of the cylindrical design of the ignition chamber and the cylindrical arrangement of the wire coil, cool fuel drops supplied in the ignition chamber act upon the incandescent ignition element. These drops are evaporated by the ignition element to gas, mixed with air and finally inflamed. Other droplets are gasified and ignited with the aid of flames produced by the ignition element. Because of this the combustion inside the ignition chamber takes place slowly, with the result that only a great ignition chamber volume is suitable for obtaining a sufficiently energy-efficient and grazing ignition flame. A great ignition chamber volume results in great overflow losses between the main combustion chamber and the ignition chamber. A great ignition chamber volume and the corresponding voluminous incandescent ignition element require, for heating during the start of the internal combustion engine, a great quantity of electrical energy and long heating times.